DE 199 084 40 A1 discloses an electromagnetic hydraulic valve of the generic type which is formed as a 3/2-way directional control valve and substantially comprises an electromagnet with an axially movable magnet armature as well as a valve part with at least two valve seats and a closing ball corresponding to at least one valve seat. The electromagnet is in this case formed by a hollow-cylindrical plastic coil former with an electrical plug contact, at least one coil winding which is accommodated in the coil former and a magnet housing which encloses the coil winding, the hollow cylinder of the plastic coil former being formed at least partly as an armature space of the magnet armature, which is lined with a non-magnetic metal sleeve. By contrast, the magnet housing of the electromagnet is formed as a cylindrical tube sleeve, one end face of which is bent into the interior of the sleeve, forming an annular base, and the other end face of which has a number of flange lugs, by which the magnet housing is connected to the plastic coil former which can be inserted into it. A metal disk molded into the plastic coil former and a pole core inserted into the hollow cylinder of the coil former additionally form an upper magnet pole of the electromagnet, while its lower magnet pole is formed by a continuation of the valve part of the hydraulic valve that can be inserted into the hollow cylinder of the coil former and is connected to the latter in a magnetically permeable manner via the base of the magnet housing. This valve part substantially comprises a hollow-cylindrical valve housing, which has a pressure connection at the end as well as a consumer connection and a tank connection, respectively formed as a radial opening in the lateral surface of said housing. The two valve seats are in this case respectively formed as an axial aperture in the base of two cup-shaped deep-drawn parts, which are fastened in the hollow cylinder of the valve housing over their circumferential surfaces with a press fit and are connected to each other by a plastic sleeve. Guided in this plastic sleeve is the loosely arranged closing ball, which is in operative connection with the magnet armature of the electromagnet by means of a tappet, the magnet armature exerting a constant prestressing force on the closing ball in the currentless state of the electromagnet, closing the pressure connection of the hydraulic valve, by a compression spring arranged between it and the pole core of the upper magnet pole. This hydraulic valve, formed as a pulling type of magnetic valve, can be inserted by the valve part, which has a number of outer sealing rings, into a complementary valve receptacle and has a separate fastening flange, which is arranged between the electromagnet and the valve part and by means of which it can be screwed on the valve receptacle in a manner sealing the pressure medium.
However, a disadvantage of this known electromagnetic hydraulic valve is that it comprises a relatively large number of individual parts, and although some parts such as the magnet housing and the valve seats can be produced without machining, others, such as for example the valve housing of the valve part as well as the magnet armature and the pole core of the upper magnet pole of the electromagnet, are of a relatively solid form and, on account of their structural configuration, can only be produced by machining methods of production. However, as a result of the relatively long machine cycle times, the necessary tools and the material used, production by machining causes considerable production expenditure, which has ultimately proven to be uneconomical. In addition, a large number of individual parts also increases the complexity of the final assembly of the hydraulic valve, so that unfavorable production costs must be expected when this known hydraulic valve is produced.